A look at the new improved TI CC2650 SensorTag

The popular development platform gets new sensors and multi-standard wireless.

When the original CC2541 SensorTag Development Kit was announced back in late 2012 it was received with much enthusiasm, with a compact key tag form factor integrating no less than:

IR temperature Sensor

Humidity Sensor

Pressure Sensor

Accelerometer

Gyroscope

Magnetometer

Making readings from all of these available via a battery-friendly Bluetooth low energy — also known as BLE and Bluetooth Smart — connection, with plentiful documentation and example sensor code and smartphone applications provided.

Given it's low cost also it's not surprising that the featured-packed SensorTag proved popular, with Python, Node.js and Node-REDsupport all being developed by the community. The latter making it trivial to rapidly prototype IoT applications via a highly intuitive graphical flow editor.

Additional sensors

The next generation CC2650 SensorTag has improved on the first generation CC2541 by increasing the sensor count to an impressive 10; a light sensor and digital microphone have been added, the IR temperature sensor has been upgraded to a device with integrated processing, there is a reed sensor in addition to a magnetometer, and the ambient temperature can be measured as well that of objects.

Multi-standard wireless

Early last year TI added support for iBeacon to the first generation hardware. Following a firmware update the CC2541 could then be switched into iBeacon mode and an example locationing app is provided for use with compatible iPhones and iPads. The new SensorTag further improves on this by also adding support for 6LowPAN, ZigBee and IEEE 802.15.4 mesh networks.

6LowPAN allows devices such as the SensorTag to join IPv6 networks, using the RFC 6282 specification that was developed with the relatively limited processing capabilities and low power wireless links of sensor networks in mind. The CC2650 SensorTag implementation comes courtesy of the popular and feature rich, open source operating system for the Internet of Things, Contiki.

ZigBee support making it easier for vendors to evaluate the SensorTag capabilities and prototype new solutions which integrate with existing ones. For example, home automation systems.

Quick start

Getting up and running is as easy as removing the battery tab from the SensorTag and loading the companion application onto an Android or iOS device. Following a quick Bluetooth scan the tag is then identified, can be connected to and data from all the sensors immediately graphed.

IoT cloud

Out-of-the-box support is provided for IBM's Internet of Things Foundation, “A fully managed, cloud-hosted service that is designed to simplify and derive the value from your IoT devices.”

Features include:

Device registration

Device and application connectivity

Securely receiving data and sending commands to devices

Storage and access to historic data

Setup is incredibly straightforward and once again you can be up and running in no time, publishing data to the web within minutes.

Should you prefer you can also use your own server infrastructure, as the SensorTag app allows a custom profile to be configured with your own MQTT broker — e.g. Mosquitto — and topic specified. Details of the MQTT field names used by the SensorTag can be found on the TI wiki.

Resources are also provided to assist those who wish to develop their own custom DevPack.

Conclusion

The CC2650 wireless MCU is said to consume 75% less energy than its predecessor, with it being claimed that a battery lifetime of 1 year+ is possible from a single coin cell battery. This in itself is impressive enough, but the additional hardware and software capabilities of the next generation SensorTag make it even more compelling.

It's also great to see that an open standard has been adopted for building IoT applications — MQTT — meaning that you're not locked-in to using a single cloud platform. Similarly, it's fantastic to see that Contiki is supported for 6LowPAN applications, with TI directly contributing back to that community. Both things which show a clear understanding of the way that things are going.

Open source (hardware and software!) advocate, Treasurer and Director of the Free and Open Source Silicon Foundation, organiser of Wuthering Bytes technology festival and founder of the Open Source Hardware User Group.